test_rvalue_ref: Small fixes

* tests/.gitignore:
* tests/CMakeLists.txt:
* tests/Makefile.am: Add test_rvalue_ref.
* tests/test_rvalue_ref.cc: Avoid [-Werror=unused-parameter]
when building with warnings=fatal.

Some files have also been reformated with clang-format in order to
make the CI tests happy. Reformated with clang-format 12, but CI
uses clang-format 10.

11 files changed, 34 insertions, 28 deletions

diff --git a/sigc++/functors/slot.h b/sigc++/functors/slot.h
index 8e9e01a..e368e86 100644
--- a/sigc++/functors/slot.h
+++ b/sigc++/functors/slot.h
@@ -151,8 +151,9 @@ struct slot_call
   static T_return call_it(slot_rep* rep, type_trait_take_t<T_arg>... a_)
   {
     auto typed_rep = static_cast<typed_slot_rep<T_functor>*>(rep);
-    return (*typed_rep->functor_).template operator()<type_trait_take_t<T_arg>...>(
-      std::forward<type_trait_take_t<T_arg>>(a_)...);
+    return (*typed_rep->functor_)
+      .template operator()<type_trait_take_t<T_arg>...>(
+        std::forward<type_trait_take_t<T_arg>>(a_)...);
   }
 
   /** Forms a function pointer from call_it().
diff --git a/sigc++/signal.h b/sigc++/signal.h
index 336bd5f..c1b0f33 100644
--- a/sigc++/signal.h
+++ b/sigc++/signal.h
@@ -364,8 +364,7 @@ public:
         continue;
 
       (sigc::internal::function_pointer_cast<call_type>(slot.rep_->call_))(
-        slot.rep_,
-        std::forward<type_trait_take_t<T_arg>>(a)...);
+        slot.rep_, std::forward<type_trait_take_t<T_arg>>(a)...);
     }
   }
 };
@@ -456,7 +455,8 @@ public:
   }
 
   /** Triggers the emission of the signal (see emit()). */
-  decltype(auto) operator()(type_trait_take_t<T_arg>... a) const {
+  decltype(auto) operator()(type_trait_take_t<T_arg>... a) const
+  {
     return emit(std::forward<type_trait_take_t<T_arg>>(a)...);
   }
 
diff --git a/tests/.gitignore b/tests/.gitignore
index 276abe2..0a788ab 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -24,6 +24,7 @@
 /test_ptr_fun
 /test_retype
 /test_retype_return
+/test_rvalue_ref
 /test_signal
 /test_signal_move
 /test_size
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 36e728b..9485b45 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -39,6 +39,7 @@ set (TEST_SOURCE_FILES
   test_ptr_fun.cc
   test_retype.cc
   test_retype_return.cc
+  test_rvalue_ref.cc
   test_signal.cc
   test_signal_move.cc
   test_size.cc
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 735d76b..b05f7b4 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -46,6 +46,7 @@ check_PROGRAMS = \
   test_ptr_fun \
   test_retype \
   test_retype_return \
+  test_rvalue_ref \
   test_signal \
   test_signal_move \
   test_size \
@@ -90,6 +91,7 @@ test_mem_fun_SOURCES         = test_mem_fun.cc $(sigc_test_util)
 test_ptr_fun_SOURCES         = test_ptr_fun.cc $(sigc_test_util)
 test_retype_SOURCES          = test_retype.cc $(sigc_test_util)
 test_retype_return_SOURCES   = test_retype_return.cc $(sigc_test_util)
+test_rvalue_ref_SOURCES      = test_rvalue_ref.cc $(sigc_test_util)
 test_signal_SOURCES          = test_signal.cc $(sigc_test_util)
 test_signal_move_SOURCES     = test_signal_move.cc $(sigc_test_util)
 test_size_SOURCES            = test_size.cc $(sigc_test_util)
diff --git a/tests/test_bind.cc b/tests/test_bind.cc
index fa8537b..0cd192c 100644
--- a/tests/test_bind.cc
+++ b/tests/test_bind.cc
@@ -70,7 +70,7 @@ struct book : public sigc::trackable
   book& operator=(book&&) = delete;
 
   std::string& get_name() { return name_; }
-  operator std::string &() { return get_name(); }
+  operator std::string&() { return get_name(); }
 
 private:
   std::string name_;
diff --git a/tests/test_cpp11_lambda.cc b/tests/test_cpp11_lambda.cc
index a8e90b2..ed12536 100644
--- a/tests/test_cpp11_lambda.cc
+++ b/tests/test_cpp11_lambda.cc
@@ -88,7 +88,7 @@ egon(std::string& str)
 struct book : public sigc::trackable
 {
   explicit book(const std::string& name) : name_(name) {}
-  operator std::string &() { return name_; }
+  operator std::string&() { return name_; }
   std::string name_;
 };
 
@@ -184,8 +184,8 @@ main(int argc, char* argv[])
   // See https://bugzilla.gnome.org/show_bug.cgi?id=669128
   //  std::cout << "((++_1)*2)(ref(a)): " << ((++_1)*2)(std::ref(a));
   //  std::cout << "; a: "                << a                    << std::endl;
-  result_stream << ([](std::reference_wrapper<int> x) -> int { return ++x * 2; }(
-                                                        std::ref(a_outer)));
+  result_stream << ([](std::reference_wrapper<int> x) -> int
+    { return ++x * 2; }(std::ref(a_outer)));
   result_stream << " " << a_outer;
   util->check_result(result_stream, "4 2");
   result_stream << ([](int& x) -> int { return ++x * 2; }(a_outer));
@@ -200,8 +200,8 @@ main(int argc, char* argv[])
 
   //  std::cout << "((--(*(&_1)))*2)(ref(a)): " << ((--(*(&_1)))*2)(std::ref(a));
   //  std::cout << "; a: "                << a                    << std::endl;
-  result_stream << ([](std::reference_wrapper<int> x) -> int { return --(*(&x)) * 2; }(
-                                                        std::ref(a_outer)));
+  result_stream << ([](std::reference_wrapper<int> x) -> int
+    { return --(*(&x)) * 2; }(std::ref(a_outer)));
   result_stream << " " << a_outer;
   util->check_result(result_stream, "6 3");
   result_stream << ([](int& x) -> int { return --(*(&x)) * 2; }(a_outer));
@@ -234,8 +234,8 @@ main(int argc, char* argv[])
   // std::cout << "(var(c) = (var(a) = _1, var(b) = _2))(2,3): "
   //          << (sigc::var(c) = (sigc::var(a) = _1, sigc::var(b) = _2))(2,3);
   // std::cout << "; a: " << a << "; b: " << b << "; c: " << c << std::endl;
-  result_stream << ([&a_outer, &b_outer, &c_outer](
-                      int x, int y) -> int { return c_outer = (a_outer = x, b_outer = y); }(2, 3));
+  result_stream << ([&a_outer, &b_outer, &c_outer](int x, int y) -> int
+    { return c_outer = (a_outer = x, b_outer = y); }(2, 3));
   result_stream << " " << a_outer << " " << b_outer << " " << c_outer;
   util->check_result(result_stream, "3 2 3 3");
 
diff --git a/tests/test_member_method_trait.cc b/tests/test_member_method_trait.cc
index 376d685..bc5c450 100644
--- a/tests/test_member_method_trait.cc
+++ b/tests/test_member_method_trait.cc
@@ -60,8 +60,8 @@ test_member_method_is_volatile()
     sigc::internal::member_method_is_volatile<decltype(&Something::some_volatile_func)>::value,
     "member_method_is_const failed to identify a volatile member method.");
 
-  static_assert(sigc::internal::member_method_is_volatile<decltype(
-                  &Something::some_const_volatile_func)>::value,
+  static_assert(sigc::internal::member_method_is_volatile<
+                  decltype(&Something::some_const_volatile_func)>::value,
     "member_method_is_const failed to identify a volatile member method.");
 }
 
diff --git a/tests/test_rvalue_ref.cc b/tests/test_rvalue_ref.cc
index b35ace1..54b04f3 100644
--- a/tests/test_rvalue_ref.cc
+++ b/tests/test_rvalue_ref.cc
@@ -2,7 +2,9 @@
 #include <iostream>
 #include <sigc++/signal.h>
 
-struct MoveableStruct {};
+struct MoveableStruct
+{
+};
 
 namespace
 {
@@ -11,10 +13,7 @@ std::ostringstream result_stream;
 
 struct foo
 {
-  void operator()(MoveableStruct &&x)
-  {
-    result_stream << "foo(MoveableStruct&&)";
-  }
+  void operator()(MoveableStruct&& /* x */) { result_stream << "foo(MoveableStruct&&)"; }
 };
 
 } // end anonymous namespace
@@ -22,7 +21,7 @@ struct foo
 void
 test_signal()
 {
-  sigc::signal<void (MoveableStruct &&)> signal;
+  sigc::signal<void(MoveableStruct &&)> signal;
   foo f;
   signal.connect(f);
   MoveableStruct x;
@@ -33,7 +32,7 @@ test_signal()
 void
 test_slot()
 {
-  sigc::slot<void (MoveableStruct &&)> slot;
+  sigc::slot<void(MoveableStruct &&)> slot;
   foo f;
   slot = f;
   MoveableStruct x;
diff --git a/tests/test_signal.cc b/tests/test_signal.cc
index b5fdaf2..d050558 100644
--- a/tests/test_signal.cc
+++ b/tests/test_signal.cc
@@ -117,10 +117,12 @@ test_clear_called_in_signal_handler()
 {
   sigc::signal<void()> sig;
   sig.connect([]() { result_stream << ", slot 1, "; });
-  sig.connect([&sig]() {
-    sig.clear();
-    result_stream << "slot 2, ";
-  });
+  sig.connect(
+    [&sig]()
+    {
+      sig.clear();
+      result_stream << "slot 2, ";
+    });
   sig.connect([]() { result_stream << "slot 3, "; });
   result_stream << sig.size();
   sig.emit();
diff --git a/tests/test_track_obj.cc b/tests/test_track_obj.cc
index cf18b7b..aefdb07 100644
--- a/tests/test_track_obj.cc
+++ b/tests/test_track_obj.cc
@@ -40,8 +40,8 @@ std::ostringstream result_stream;
 struct book : public sigc::trackable
 {
   explicit book(const std::string& name) : name_(name) {}
-  operator std::string &() { return name_; }
-  operator const std::string &() const { return name_; }
+  operator std::string&() { return name_; }
+  operator const std::string&() const { return name_; }
   std::string name_;
 };